<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>jQuery实现CheckBox全选、全不选</title>
    <script src="http://code.jquery.com/jquery-1.4.4.min.js" type="text/javascript"></script>    <script type="text/javascript">
    $(function() {
        $("#checkAll").click(function() {
            $('input[name="subBox"]').attr("checked",this.checked);
        });
        var $subBox = $("input[name='subBox']");
        $subBox.click(function(){
            $("#checkAll").attr("checked",$subBox.length == $("input[name='subBox']:checked").length ? true : false);
        });
    });
</script>

</head>
<body>
<div>
    <input id="checkAll" type="checkbox" />全选
    <input name="subBox" type="checkbox" />项1
    <input name="subBox" type="checkbox" />项2
    <input name="subBox" type="checkbox" />项3
    <input name="subBox" type="checkbox" />项4
</div>
</body>
</html>